Hydraulic well pumping method

ABSTRACT

Method for operating a downhole hydraulic well pumping system. One aspect of the invention is directed to a method for injecting spent power fluid into a lower or upper stratum of the ground while extracting energy from the power fluid in order to pump oil from another stratum to the surface of the ground. This expedient enables the spent power fluid to be advantageously used as a water flooding agent, and further enables chemical treatment of the upper or lower stratum to be carried out by utilizing the spent power fluid as the vehicle for transporting the chemical into the stratum. The associated apparatus comprehends a new combination of a production unit having a piston and control valve assembly which forms an engine for actuating a downhole pump. The piston and control valve assembly cooperates with the downhole pump motor in a manner to enable spent power fluid from the engine to be injected through a standing valve assembly into a stratum located below or above the producing formation.

United States Patent Patented Dec. 14, 1971 3 Sheets-Sheet l lill/14% xIl l my' f/ :w//

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Patented Dec. 14, 1971 ll HYDRAULIC WELL PIUMIPIING MIE'II'IHIODREFERENCE TO RELATED APPLICATION BACKGROUND OIF THE INVENTION Variousfluid operated deep well pumps, sometime called hydraulic oil wellpumping or production units, are`known to those skilled in the art. Theproduction units generally include a valve system which receives powerfluid from a pump located above the surface of the ground and whichcontrollably supplies the power fluid to an engine. The enginereciprocates a piston rod which in turn actuates a fluid pump. The spentpower fluid is generally comingled with the production fluid and forcedto return to the surface of the ground by the action ofthe pump. Variousprior art control valve and engine assemblies have proven successful foruse in deep wells.

In the production of oil and other fluids from deep wells havingmultiple producing formations, it may be desirable to dispose of eitherfresh or salt water which is sometime produced along with oil. Thedisposal of this salt water is often costly. On the other hand, in waterflooding programs and the like, it may be necessary to provide a sourceof water in order to flood various oil producing stratum with a low costdisposable fluid. Under these circumstances it may be necessary topurchase the water since its use in a controlled program results in aneconomic gain in the form of increased production. An advantageousexpedient recognized by the oil industry is the injection of gases,steam, salt or fresh water, as well as other treating chemicals in orderto produce various oil Strata.

SUMMARY OF THE INVENTION The present invention comprehends a method fortransferring spent power fluid from a downhole pump associated with aproduction formation into a water flood zone. The spent power fluidincludes oil or water which is eliminated from a downhole pump inproducing oil from an oil production stratum. The water flood zone orstratum may be located either above or below the production formation.ln exemplifying the present invention, a standing valve assembly is usedin conjunction with other apparatus as an illustration. The valve isplaced in communication with a production formation with the valveassembly being separated from the water flood zone and the productionformation by means ofa packer. The valve cooperates with a hydraulic oilwell production unit and includes telescopingly arranged parts havingpassageways therein which normally permit the flow of produced oilthrough the valve and into the pump of the production unit where thepump lifts the produced oil to the surface of the earth. Simultaneously,the valve permits the spent power fluid from the engine to flow into awater flood zone, thereby precluding comingling of the spent power fluidwith the produced oil as well as preventing commingling of the waterflood zone with the production zone. The valve is selectively shifted toa shut off nonproducing position in order to enable removal of thebottom hole production unit while precluding commingling of the twoformations. In this latter position, the telescoping coacting parts ofthe standing valve assembly precludes the flow of fluid between theproduction formation and the water flood zone to thereby enablereplacement of the bottom hole pump as well as to make possible thechemical treatment of either zone and to permit bottom hole pressuretesting of either zone and to permit bottom hole pressure testing ofeither zone to be carried out separately from one another.

Alternatively` the pumping system could include the before mentionedstanding valve in combination with a production unit having a piston andcontrol valve which utilizes the valve assembly and motor into a singlereciprocating piston and control valve arrangement. The piston andcontrol valve which forms the engine and valve assembly includes ahollow connecting rod reciprocatingly attached to the piston of aconventional double acting oil production pump. The hollow rod continuesfrom the engine` through the pump. and into fluid communication with thestanding valve by means of an isolation tube and stinger pipe.Production fluid from the standing valve r flows about an annulus formedbetween the stinger tube and the standing valve and into the pump unit,while the spent power fluid flows through the stinger tube and through aseries of passageways provided within the standing valve to where it isultimately dissipated into a water flood zone, or the like.

It is therefore an object of the present invention to provide a methodof utilizing the spent power Afluid from a bottom hole production unitfor water flood control.

Another object of the present invention is to provide a method ofexhausting spent power fluid from a bottom hole production unit withoutusing a closed power fluid system to prevent commingling the productionfluid and the spent power fluid.

A further object of the present inventionis to provide a method ofutilizing water which is produced along with oil from one formation asthe power fluid for actuating a bottom hole pump as well as using thespent power fluid for a water flood agent in another stratum.

A still further object of the present invention is the provision of amethod for utilizing spent power fluid from a down hole production unitin order to treat another production zone.

Another object of the present invention is the provision of an improvedmethod for a bottomhole pumping system which includes a production unitcomprised of the combination which includes a piston and control valveintegrated into a single moving unit, and which provides an engine whichreciprocates a pump, with the spent power fluid from the engine beingcontrollably flowed into a `disposal zone of the well by means of animproved standing valve assembly.

These and other objects of the present invention will become readilyapparent to those skilled in the art upon reading the following detaileddescription and by referringto the accompanying drawings.

The above objects are attained in accordance with the present inventionby the provision of a method which is carried out essentially as setforth in the above abstract.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. lA and IB are fragmentaryvertical cross-sectional views illustrating the hydraulic well pumpingsystem of the present invention;

FIG. 2 is an enlarged vertical cross-sectional view showing a portionofthe device seen in FIGS. IA and 1B;

FIG. 3 is a fragmentary vertical cross-sectional view of part ofthedevice seen in FIG. 2, but shown in a different operating position;

FIG. d is an enlarged fragmentary `cross-sectional view of part of thedevice seen in the foregoing figures;

FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 2; and

FIG. 6 is a cross-sectional view taken along line 6-6 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT Looking now to the details ofthe drawing, and in particular to FIGS. IA and IB, in conjunction withthe remaining figures, there is seen an oil producing stratum 6, a waterflood zone 7, a vertical borehole having a casing 8 coextensiveherewith, and with a packer 9 separating the two strata from oneanother. The packer is attached to a foot l0 having power tubing IIupwardly depending therefrom and with the hydraulic well pumping systembeing operatively connected to the piping and to the foot. Slidablylocated within the power tubing there is seen a portion of the hydraulicwell pumping system which includes a production unit having an aperturednose 12 about which there is sealingly positioned spaced apart packers14 located on the power fluid inlet 16. The inlet diverges into acircumferentially extending packer seal assembly 18 which is providedwith a circumferentially extending groove having an O-ring 20 sealinglylocated therein. The O-ring is slidably received in close tolerancefitting 'relationship within an O-ring collar 22. The packer sealassembly is connected to a stroke chamber sub 24 which in turn isthreadedly attached to a barrel, generally indicated by the numeral at25. The stroke chamber sub forms a chamber 26 within which he terminalend of an input rod 28 reciprocates. The stroke chamber reduces indiameter into an input rod passageway 30 which includes a packing glandreceived within a counterbore 32 at the lower extremity thereof. Theinput rod is provided with a longitudinally extending hollow passageway34 therethrough and is connected by inlet boss 36 to a novel piston andcontrol valve arrangement generally illustrated by the arrow at numeral40. The piston and control valve reciprocates within a cylinder formedinternally of the barrel. The piston includes expansible metal sealingrings 38, 38 disposed at the upper and lower extremities thereof. Thedetails of the piston and control valve will be discussed more fullylater on.

From the piston a connecting rod extends downwardly from an outlet boss41 in a manner as best seen as 42. The connecting rod interconnects hepiston with a double acting pump 44. The details of the double actingpump are not set forth in detail, but generally the pump includesupstroke exhaust ports 45 and downstroke exhaust ports 46. Furtherdetails of pump are not deemed necessary for a full comprehension of theinvention since the design and construction of several such pumps arewell known to those skilled in the art.

A hollow discharge rod extends from the lower extremity of the pump at47 where it is slidably received in a reciprocative manner within anisolation tube 48 with the free end of the rod terminating therein. Thepump inlet is in communication with the chamber fonned between the outerperipheral wall surface of the isolation tube and the inside peripheralwall surface of the barrel.

A bottom plug 50 is threadedly attached to the lower end of the barreland includes a multiplicity of longitudinally extending radially spacedapart drilled passageways 51` An isolation tube counterbore S4 sealinglyreceives the lower depending free end of the isolation tube in closefitting relationship therewith. About the isolation tube there iscircumferentially disposed a groove having O-ring 52 fitted therein. Thebottom plug includes a shoulder 56 which sealingly cooperates with thepump seat 56 The isolation tube counterbore reduces in diameter andcontinues as the lowermost portion of the hydraulic pump unit, alsocalled a stinger, as seen at numeral 60. The outside peripheral wallface of the depending marginal end portion of the stinger is providedwith O-ring seals 61 which are slidably received within the illustratedshoulder of the counterbore.

A standing valve assembly, generally indicated by the numeral 62 isslidably received within counterbore 64 of the foot and includes thebefore mentioned pump seat. The standing valve further includes atelescoped member 83 which is made integrally with and downwardlydepending from the before mentioned pump seat, and which istelescopingly received within a main body member 70 thereby leaving anannular area 66 between the main body member and the foot. The main bodymember is comprised of a lower portion 68 which is screw threaded ontoan upper portion 74 by means of threads 72. The two spaced apartenlargements are seen to be formed by members 74, 76 which cooperate toprovide an annulus 78 therebetween. Enlargement 74 seats against thefoot as seen at 80 while enlargement 76 is provided with seal means inthe form of a circumferentially extending groove having an O-ring 82therein. Pump seat 57 is provided with a lower hollow terminal end whichis screw threaded at 84 into engagement with a similarly threaded plug86. The lower extremity of the plug includes biasing means 88 whichbiases the telescoped pump seat member in an upward direction. Cavityflow passageway 90 communicates with ports 92, 93 and with chamber 94;while port 96 located within the foot communicates with annulus 78,ports 97, 98, 51, and annulus when the valve is in the operativeposition. Port 99 is flow connected to port 99 which flow communicatesthe stinger with the lower formation by means of counterbore 64.

Cavity flow passageway 90 also communicates with passageway 101 which isflow connected to the production tubing 102 and which carries productionfluid from formation 6 to the surface of the ground.

Looking more particularly to the details of the integrated or unitizedpiston and control valve 40 (which is shown in greater detail in FIGS. 2and 3) there is seen the before mentioned hollow input rod 28 and upperboss 36 at the uppermost portion of the figures. The boss has a shouldernear numeral 104 which abuts the uppermost face of the piston 40.O-rings 106 seal the downwardly projecting portion of the bass which isreceived within counterbore 108 of the uppermost portion 110 of thepiston. The threaded connection l 12 rigidly aftixes the boss of thecylinder. The lowermost end of the boss forms a valve seat 114 at thelower extremity of the passageway 116. Radially extending passageways118 provide fluid flow into drilled passageway 120.

The longitudinally extending drilled passageways 122 connect the chamberformed within the barrel above the piston to radial passageways 124.Second radial passageways 126 flow connect to the longitudinallyextending passageways 128 by means of the chamber formed within thesmall cylinder 130. Piston 132 has a lower portion in the form of aMaltese Cross having radiating guides or fins 134 thereon which areslidably received in close fitting relationship within the smallcylinder 130. The head 136 of the small piston seats against valve seatmember 114. The lower extremity of the Maltese Cross at 138 freely abutsagainst the uppermost face of intermediate piston 140. Piston 140includes an upper portion 142, lower portion 144, connected together bya reduced diameter portion which leaves an annulus 146 therebetween.Piston 132 and 140 could be made into a single member, however thisparticular construction is preferred since many alignment problems areeliminated by the illustrated construction.

lntennediate piston 140 reciprocates within intermediate cylinder 148while the upper or small piston 132 reeiprocates within the smallcylinder 130, with each piston coacting together in a reciprocatingmanner as a single unit. Radial passageway 150 is fluid connected tooutlet 151 by means of longitudinal passageway 152. Lower boss 154 isthreadedly attached at 154 to the main body ofthe piston. Radial ports158 and are provided in the boss. A counterbore receives the lower bossin a manner similar to the upper boss 36. A drilled passageway 162extends longitudinally through the piston and reciprocatingly receivespilot ,valve 164 therein. The pilot valve includes upper reducedterminal end 166, enlarged upper portion 168, spiral undercut 170,reduced diameter portion 172, lower enlarged portion 174, and lowerterminal end 167. As seen at 166, one terminal end of the pilot valvealways protrudes from he piston and alternately engages or impactsagainst the packing gland 32 (FIG. l), or the packing gland of the motor(not shown).

OPERATION ln operation the engine (i.e., the combination piston andvalve means) and pump are assembled into the illustrated production unitwhich is used in a system of the parallel free type. The production unitcan also be used in a multiplicity of other systems. The entireproduction unit can be circulated into and out of the piping 11 bycontrolling the direction of ow through the piping and the productionreturn line 102. With the flow of power fluid being in a downwarddirection through the piping 11, and the production unit assembled intoa unitary apparatus with the unit being placed within the piping in theillustrated manner of FlGS. 1A and 1B, the bottom plug seats within thepump seat 37 of the standing valve, with mutual contact being attainedtherebetween at 3b. Power fluid flows down through the piping and intothe apertured nose, through the paclter seal assembly, and into thestroke chamber. The (l-ring collar prevents power fluid from flowingexternally between the unit and the piping. The flow must thereforecontinue through the uppermost portion of the reciprocating hollow inputrod 29 and into the piston and control valve assembly, where the powerfluid reciprocatingly actuates piston titl within the polished portionof the barrel.

In operation of the combination piston and control valve, and asparticularly seen in FIG. 2, the power fluid enters upper boss 3d wherethe main flow continues through radial passageway 11119, longitudinalpassageway 11211), into the annulus me, and through outlet i511 wherethe power fluid exerts a force upon the bottom of the piston to therebyforce the piston in an upward direction within the barrel 23. Upper andlower rings 39 and 39' prevent escape of fluid between the piston andbarrel. Flow of fluid through passageway H79, about the annulus formedby the reduced diameter portion of the pilot valve at 1172, and into thearea below piston portion 11M exerts an upward pressure upon the pistonwill. Noting the difference in area of intermediate piston at 11M andsmall piston at H36, it is seen that the area of piston ldd with respectto piston i3d is unequal and accordingly the small piston 1132 ismaintained forcibly seated against valve seat 111143. The contouredvalve portion 1136 of the small piston together with the cooperativeaction between small cylinder 11311) and the upper cylindrical portionof the piston prevents escape of fluid therethrough. This cooperativeaction between the recited elements provides a double seal.

As the piston d@ travels in an upward direction in order to assume theillustrated position of FIG. 2, the fluid within chamber 33 must escapeto allow movement of the piston into the upper portion of the cylinderas the piston travels toward packing gland 32. This is accomplished bythe provision of passageways B22 which are interconnected to passageways128 by means of radial passageways 1124, 1126, and to the free portionof cylinder 130 (i.e., between the elements or fins of the MalteseCross) in order to permit the flow of fluid through radial passageway1160 and through the hollow connecting rod 42. As the piston travels inthis manner in an upward direction, it reaches its limit of travel (FIG.2) whereupon the upper terminal end of the pilot valve at lbti contactsthe packing gland 32 to thereby drive the pilot valve in a downwarddirection tothe position illustrated in FIG. 3.

Looking now to the details of FIG. 3 in conjunction with FIGS. 1l and 2,and in order to explain the action of the engine valve system on thedownstroke, those skilled in the art will now realize that power fluidfrom the hollow passageway 34 flows against small piston 1132 therebydriving it in a downward direction alongwith the intermediate piston Mwithin the cylinder M9 until the lowermost portion 11M of the pistonabuts member i341. This action brings the device into the configurationof FIG. 3 and permits the flow of fluid to occur through passageway B24,H22, whereupon the fluid pressure is exerted against the upper ace ofthe piston thereby driving the main piston d@ in a downward directionwhere the piston assumes the position of FIG. 3. Fluid located below themain piston and above the seal pack-off liner (not shown but located inthe area generally indicated by numeral 11412) must exhaust therefrom inorder to enable the piston to travel downwardly within the barrel. Thisis accomplished by the provision of passageway 1152 which permits fluidflow into the cylinder H30, through radial passageway R26, longitudinalpassageway 1123, radial passageway 160, and through the hollowconnecting rod 412, where the fluid ultimately reaches the isolationtube. The combination piston and control valve, or engine, continues toreciprocate in this manner so long as a power source is supplied to theengine and valve assembly, and so long as the outlet d2 is at asufficiently reduced pressure with respect to he fluid in passageway 3d.

Connecting rod l2 reciprocatingly actuates the double acting pump Mlwith the pump inlet being in communication with the annulus providedbetween the isolation tube 48 and the barrel. Pump outlets Q13 and 4ddeliver fluid in a downward direction into annulus 90, up throughpassageway 101, and into the production tubing 102 where the fluid isforced to ground level. The spent power fluid from hollow connecting rodt2 flows through central passag-eways located in the pump where it exitsat the depending terminal end of the hollow discharge rod as seen at41.7 in FIG. 11B. Since the isolation tube 413 is sealed withincounterbore 5d `of the bottom plug 50 the fluid must continue to flowthrough the lower hollow depending end of' the plug and through thestinger as seen at 58, whereupon the fluid then flows through radialpassageways 99 and 99', into the annulus between the main body memberand the foot at 66, to where the spent power fluid then flows throughthe perforations 7 below the packer 9 and into the water flood zone 7.

Still looking to the details of FIGS. 1A and 1B it will now be realizedthat production fluid from formation 6 flows into the perforations t toprovide a production fluid level 141 within the casing 9. The productionfluid enters the foot through radial passageway 96 where the fluid flowsthrough annulus 79, through radial ports 97, 99 and into the annulusabout the lower depending end of the stinger where the fluid is thenfree to flow upwardly through the spaced apart radial production fluidinlet passageways 511 and into the barrel of the pump.

When it is desired to retrieve the production unit, the power fluid flowis discontinued and circulation is reversed by applying a positivepressure upon the production return line. This action simultaneouslyforces the production unit and the pump seat of the free standing valvein an upward direction whereupon the unit is then forced from the pumpseat and to the ground level as fluid is pumped through the productionreturn line. It will be noted that the pump seat follows the pump for alimited distance when fluid pressure is exerted through radialpassageway 92, longitudinal passageway 93, and into the chamber 94. Thisaction is due to the difference in area of the pump which is exposed tothe fluid pressure from production line 102, which forces telescopingmember 57 to move upward with respect to the main body member 74 therebymisaligning ports 97 with respect to ports 93 and misaligning ports 99with respect to ports 99'. Spring 88 assures the continued misalignmentof the ports to thereby preclude comingling of liquid from thewaterilood zone 7 with fluid from the production zone 6. When theproduction unit is pumped back into operative position, the lowermostdepending end portion, or stinger, of the plug again enters the pumpseat thereby forcing the standing vallve back into the open position ofFIG. llB.

The free standing valve of the present invention also permits either orboth zones 6 and/or 7 to be simultaneously treated with variouschemicals while using an isolation tool and while the production unit isremoved from the piping. This operation is best carried out bypositioning an isolation tool onto the standing valve in order to exposethe zone to be treated while blocking off the remaining zone. When thetreatment has been accomplished, the isolation tool is pumped out of thehole. As the tool is pumped from the hole, the standing valve will shiftto the closed position prior to the tool leaving the valve seat, inaccordance with the previously described operation of the valve inconjunction with the pump.

It is contemplated to use the present invention in combination withvarious operations other than. oil production. In sulfur production, forexample, superheated water can be used as the power fluid with the spentpower fluid being injected below the molten sulfur n order to placeadditional sulfur into solution. Accordingly, the use of water as thepower fluid in order to produce oil from an oil bearing formation shouldbe considered as one of many exemplifrcations of the present invention.

The foregoing is considered as illustrative only of the principles oftheinvention.

Iclaim:

l. ln a borehole which penetrates two different zones, at least one ofwhich is fluid bearing, wherein he borehole has disposed therein a fluidactuated downhole pump assembly. said pump assembly including a motorand a production pump, said production pump lifts produced fluid from afluid producing zone to the surface of` the ground, the method of theproducing fluid from a first of said zones which is fluid bearing whilesimultaneously treating a second of said zones, comprising the steps of:

l. flow connecting the motor of said fluid actuated downhole pumpassembly to a source of power fluid wherein the power fluid source islocated uphole of the two zones;

2. flow connecting the produced fluid from the first of said zones to tosaid second of said zones;

3. flow connecting the produced fluid for the first of said zones to theproduction pump ofsaid pump assembly; and

4. isolating the first zone from the second zone to prevent productionfluid from flowing from one to the other.

2. The method of claim l and further including the step of using wateras the source of power fluid in order to water flood said second zone.

3. The method of claim ll, and further including the step ofincorporating a treating chemical into the power fluid in order tosubject said second zone to chemical treatment.

4. The method of claim l and further including carrying out step (4) bypacing a packer means between the first and second zone so as to isolateeach zone from one another; and carrying outstep (2) by flow connectingthe spent power fluid from the downhole pump, through the packer means,and to the recited second zone.

5. The method of claim 4, and further includingthestep of includingmeans by which each recited zone is isolated from one another uponremoval of the pump.

6. A method of producing fluid from a first fluid-bearing stratumpenetrated by the well wherein a downhole fluid actuated pump lifts theproduced fluid from the first stratum to the surface of the earth;comprising the steps of:

l. isolating the first stratum from the second stratum by using a packermeans;

2. flow connecting a power fluid source to the fluid actuated Pump;

3. flow connecting the spent power fluid from the fluid actuated pumpthrough the packer means and into the second stratum.

7. The method of claim 6, and further including the step of using wateras the power fluid source in order to water flood said second stratum.

8. The method of claim 6 and further including the step of using atreating chemical as the power fluid source in order to subject saidsecond stratum to chemical treatment.

9. The method of claim 6, and further including the step of includingmeans by which each recited stratum is isolated from one another uponremoval of the pump.

l0. The method of claim 6, and further including the step of injecting atreating agent into the power fluid when it is desired to treat thesecond stratum with said treating agent.

llllllld 02U P0050 I UNITED STATES PATENT OF FICE CERTIFICATE OFCORRECTION Patent No. 3 ,oef/,OEE i Dated DECEMBER ll. i971 Inventms)GEORGE K. EoEDEE I It .is certified that error appears in theabove-identified 'patent and that said Letters Patent are herebycorrected as shown below:

Claim l, line 2, substitute the-- for` "he";

'Line lh, substitute 2. flow 4connecting the spent power fluid from saidmotor` to said second of said zones;- for' "2. flow connecting theproduced fluid from the first of said zones to to said seoond of saidzones";

Lin-e lo, substitute #-fr'om--for "for".

Claim 3; line i, Substitute Claim 1 for "Claim 11".

Claim 6, line 2, after stratum" insert --of a well while simultaneouslyinjecting fluid into a second stratum- Signed and sealed this 20th dayof June 1972.

(SEALl Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attest-.ing Officer lCommissioner' of Patents

1. In a borehole which penetrates two different zones, at least one ofwhich is fluid bearing, wherein the borehole has disposed therein afluid actuated downhole pump assembly, said pump assembly including amotor and a production pump, said production pump lifts produced fluidfrom a fluid producing zone to the surface of the ground, the method ofproducing fluid from a first of said zones which is fluid bearing whilesimultaneously treating a second of said zones, comprising the stepsof:
 1. flow connecting the motor of said fluid actuated downhole pumpassembly to a source of power fluid wherein the power fluid source islocated uphole of the two zones;
 2. flow connecting the spent powerfluid from said motor to said second of said zones;
 3. flow connectingthe produced fluid from the first of said zones to the production pumpof said pump assembly; and
 4. isolating the first zone from the secondzone to prevent production fluid from flowing from one to the other. 2.flow connecting the spent power fluid from said motor to said second ofsaid zones;
 2. The method of claim 1 and further including the step ofusing water as the source of power fluid in order to water flood saidsecond zone.
 2. flow connecting a power fluid source to the fluidactuated pump;
 3. flow connecting the spent power fluid from the fluidactuated pump through the packer means and into the second stratum. 3.The method of claim 1, and further including the step of incorporating atreating chemical into the power fluid in order to subject said secondzone to chemical treatment.
 3. flow connecting the produced fluid fromthe first of said zones to the production pump of said pump assembly;and
 4. isolating the first zone from the second zone to preventproduction fluid from flowing from one to the other.
 4. The method ofclaim 1 and further including carrying out step (4) by pacing a packermeans between the first and second zone so as to isolate each zone fromone another; and carrying out step (2) by flow connecting the spentpower fluid from the downhole pump, througH the packer means, and to therecited second zone.
 5. The method of claim 4, and further including thestep of including means by which each recited zone is isolated from oneanother upon removal of the pump.
 6. A method of producing fluid from afirst fluid-bearing stratum of a well simultaneously injecting fluidinto a second stratum penetrated by the well wherein a downhole fluidactuated pump lifts the produced fluid from the first stratum to thesurface of the earth; comprising the steps of:
 7. The method of claim 6,and further including the step of using water as the power fluid sourcein order to water flood said second stratum.
 8. The method of claim 6and further including the step of using a treating chemical as the powerfluid source in order to subject said second stratum to chemicaltreatment.
 9. The method of claim 6, and further including the step ofincluding means by which each recited stratum is isolated from oneanother upon removal of the pump.
 10. The method of claim 6, and furtherincluding the step of injecting a treating agent into the power fluidwhen it is desired to treat the second stratum with said treating agent.